diff options
Diffstat (limited to 'pod/perlfunc.pod')
| -rw-r--r-- | pod/perlfunc.pod | 80 |
1 files changed, 40 insertions, 40 deletions
diff --git a/pod/perlfunc.pod b/pod/perlfunc.pod index e8f92d3c79..081709a174 100644 --- a/pod/perlfunc.pod +++ b/pod/perlfunc.pod @@ -335,7 +335,7 @@ following a minus are interpreted as file tests. The C<-T> and C<-B> switches work as follows. The first block or so of the file is examined for odd characters such as strange control codes or -characters with the high bit set. If too many strange characters (E<gt>30%) +characters with the high bit set. If too many strange characters (>30%) are found, it's a C<-B> file, otherwise it's a C<-T> file. Also, any file containing null in the first block is considered a binary file. If C<-T> or C<-B> is used on a filehandle, the current stdio buffer is examined @@ -544,7 +544,7 @@ arguments with which the subroutine was invoked. Be aware that the optimizer might have optimized call frames away before C<caller> had a chance to get the information. That means that C<caller(N)> might not return information about the call frame you expect it do, for -C<N E<gt> 1>. In particular, C<@DB::args> might have information from the +C<< N > 1 >>. In particular, C<@DB::args> might have information from the previous time C<caller> was called. =item chdir EXPR @@ -1002,8 +1002,8 @@ lookup: Outside an C<eval>, prints the value of LIST to C<STDERR> and exits with the current value of C<$!> (errno). If C<$!> is C<0>, -exits with the value of C<($? E<gt>E<gt> 8)> (backtick `command` -status). If C<($? E<gt>E<gt> 8)> is C<0>, exits with C<255>. Inside +exits with the value of C<<< ($? >> 8) >>> (backtick `command` +status). If C<<< ($? >> 8) >>> is C<0>, exits with C<255>. Inside an C<eval(),> the error message is stuffed into C<$@> and the C<eval> is terminated with the undefined value. This makes C<die> the way to raise an exception. @@ -1217,12 +1217,12 @@ as terminals may lose the end-of-file condition if you do. An C<eof> without an argument uses the last file read. Using C<eof()> with empty parentheses is very different. It refers to the pseudo file formed from the files listed on the command line and accessed via the -C<E<lt>E<gt>> operator. Since C<E<lt>E<gt>> isn't explicitly opened, -as a normal filehandle is, an C<eof()> before C<E<lt>E<gt>> has been +C<< <> >> operator. Since C<< <> >> isn't explicitly opened, +as a normal filehandle is, an C<eof()> before C<< <> >> has been used will cause C<@ARGV> to be examined to determine if input is available. -In a C<while (E<lt>E<gt>)> loop, C<eof> or C<eof(ARGV)> can be used to +In a C<< while (<>) >> loop, C<eof> or C<eof(ARGV)> can be used to detect the end of each file, C<eof()> will only detect the end of the last file. Examples: @@ -1465,7 +1465,7 @@ operation is a hash or array key lookup or subroutine name: Although the deepest nested array or hash will not spring into existence just because its existence was tested, any intervening ones will. -Thus C<$ref-E<gt>{"A"}> and C<$ref-E<gt>{"A"}-E<gt>{"B"}> will spring +Thus C<< $ref->{"A"} >> and C<< $ref->{"A"}->{"B"} >> will spring into existence due to the existence test for the $key element above. This happens anywhere the arrow operator is used, including even: @@ -1933,8 +1933,8 @@ Returns the socket option requested, or undef if there is an error. Returns the value of EXPR with filename expansions such as the standard Unix shell F</bin/csh> would do. This is the internal function -implementing the C<E<lt>*.cE<gt>> operator, but you can use it directly. -If EXPR is omitted, C<$_> is used. The C<E<lt>*.cE<gt>> operator is +implementing the C<< <*.c> >> operator, but you can use it directly. +If EXPR is omitted, C<$_> is used. The C<< <*.c> >> operator is discussed in more detail in L<perlop/"I/O Operators">. Beginning with v5.6.0, this operator is implemented using the standard @@ -2109,7 +2109,7 @@ Implements the ioctl(2) function. You'll probably first have to say to get the correct function definitions. If F<ioctl.ph> doesn't exist or doesn't have the correct definitions you'll have to roll your -own, based on your C header files such as F<E<lt>sys/ioctl.hE<gt>>. +own, based on your C header files such as F<< <sys/ioctl.h> >>. (There is a Perl script called B<h2ph> that comes with the Perl kit that may help you in this, but it's nontrivial.) SCALAR will be read and/or written depending on the FUNCTION--a pointer to the string value of SCALAR @@ -2553,24 +2553,24 @@ for this purpose; so if you're using C<my>, specify EXPR in your call to open.) See L<perlopentut> for a kinder, gentler explanation of opening files. -If MODE is C<'E<lt>'> or nothing, the file is opened for input. -If MODE is C<'E<gt>'>, the file is truncated and opened for -output, being created if necessary. If MODE is C<'E<gt>E<gt>'>, +If MODE is C<< '<' >> or nothing, the file is opened for input. +If MODE is C<< '>' >>, the file is truncated and opened for +output, being created if necessary. If MODE is C<<< '>>' >>>, the file is opened for appending, again being created if necessary. -You can put a C<'+'> in front of the C<'E<gt>'> or C<'E<lt>'> to indicate that -you want both read and write access to the file; thus C<'+E<lt>'> is almost -always preferred for read/write updates--the C<'+E<gt>'> mode would clobber the +You can put a C<'+'> in front of the C<< '>' >> or C<< '<' >> to indicate that +you want both read and write access to the file; thus C<< '+<' >> is almost +always preferred for read/write updates--the C<< '+>' >> mode would clobber the file first. You can't usually use either read-write mode for updating textfiles, since they have variable length records. See the B<-i> switch in L<perlrun> for a better approach. The file is created with permissions of C<0666> modified by the process' C<umask> value. -These various prefixes correspond to the fopen(3) modes of C<'r'>, C<'r+'>, C<'w'>, -C<'w+'>, C<'a'>, and C<'a+'>. +These various prefixes correspond to the fopen(3) modes of C<'r'>, C<'r+'>, +C<'w'>, C<'w+'>, C<'a'>, and C<'a+'>. In the 2-arguments (and 1-argument) form of the call the mode and filename should be concatenated (in this order), possibly separated by -spaces. It is possible to omit the mode if the mode is C<'E<lt>'>. +spaces. It is possible to omit the mode if the mode is C<< '<' >>. If the filename begins with C<'|'>, the filename is interpreted as a command to which output is to be piped, and if the filename ends with a @@ -2590,7 +2590,7 @@ that pipes both in I<and> out, but see L<IPC::Open2>, L<IPC::Open3>, and L<perlipc/"Bidirectional Communication"> for alternatives.) In the 2-arguments (and 1-argument) form opening C<'-'> opens STDIN -and opening C<'E<gt>-'> opens STDOUT. +and opening C<< '>-' >> opens STDOUT. Open returns nonzero upon success, the undefined value otherwise. If the C<open> @@ -2662,10 +2662,10 @@ Examples: } You may also, in the Bourne shell tradition, specify an EXPR beginning -with C<'E<gt>&'>, in which case the rest of the string is interpreted as the +with C<< '>&' >>, in which case the rest of the string is interpreted as the name of a filehandle (or file descriptor, if numeric) to be -duped and opened. You may use C<&> after C<E<gt>>, C<E<gt>E<gt>>, -C<E<lt>>, C<+E<gt>>, C<+E<gt>E<gt>>, and C<+E<lt>>. The +duped and opened. You may use C<&> after C<< > >>, C<<< >> >>>, +C<< < >>, C<< +> >>, C<<< +>> >>>, and C<< +< >>. The mode you specify should match the mode of the original filehandle. (Duping a filehandle does not take into account any existing contents of stdio buffers.) Duping file handles is not yet supported for 3-argument @@ -2696,7 +2696,7 @@ STDERR: print STDOUT "stdout 2\n"; print STDERR "stderr 2\n"; -If you specify C<'E<lt>&=N'>, where C<N> is a number, then Perl will do an +If you specify C<< '<&=N' >>, where C<N> is a number, then Perl will do an equivalent of C's C<fdopen> of that file descriptor; this is more parsimonious of file descriptors. For example: @@ -3092,10 +3092,10 @@ are inherently non-portable between processors and operating systems because they obey the native byteorder and endianness. For example a 4-byte integer 0x12345678 (305419896 decimal) be ordered natively (arranged in and handled by the CPU registers) into bytes as - + 0x12 0x34 0x56 0x78 # little-endian 0x78 0x56 0x34 0x12 # big-endian - + Basically, the Intel, Alpha, and VAX CPUs are little-endian, while everybody else, for example Motorola m68k/88k, PPC, Sparc, HP PA, Power, and Cray are big-endian. MIPS can be either: Digital used it @@ -3105,12 +3105,12 @@ The names `big-endian' and `little-endian' are comic references to the classic "Gulliver's Travels" (via the paper "On Holy Wars and a Plea for Peace" by Danny Cohen, USC/ISI IEN 137, April 1, 1980) and the egg-eating habits of the Lilliputians. - + Some systems may have even weirder byte orders such as - + 0x56 0x78 0x12 0x34 0x34 0x12 0x78 0x56 - + You can see your system's preference with print join(" ", map { sprintf "%#02x", $_ } @@ -3432,8 +3432,8 @@ When C<$/> is set to C<undef>, when readline() is in scalar context (i.e. file slurp mode), and when an empty file is read, it returns C<''> the first time, followed by C<undef> subsequently. -This is the internal function implementing the C<E<lt>EXPRE<gt>> -operator, but you can use it directly. The C<E<lt>EXPRE<gt>> +This is the internal function implementing the C<< <EXPR> >> +operator, but you can use it directly. The C<< <EXPR> >> operator is discussed in more detail in L<perlop/"I/O Operators">. $line = <STDIN>; @@ -3769,7 +3769,7 @@ This is also useful for applications emulating C<tail -f>. Once you hit EOF on your read, and then sleep for a while, you might have to stick in a seek() to reset things. The C<seek> doesn't change the current position, but it I<does> clear the end-of-file condition on the handle, so that the -next C<E<lt>FILEE<gt>> makes Perl try again to read something. We hope. +next C<< <FILE> >> makes Perl try again to read something. We hope. If that doesn't work (some stdios are particularly cantankerous), then you may need something more like this: @@ -3863,7 +3863,7 @@ You can effect a sleep of 250 milliseconds this way: select(undef, undef, undef, 0.25); B<WARNING>: One should not attempt to mix buffered I/O (like C<read> -or E<lt>FHE<gt>) with C<select>, except as permitted by POSIX, and even +or <FH>) with C<select>, except as permitted by POSIX, and even then only on POSIX systems. You have to use C<sysread> instead. =item semctl ID,SEMNUM,CMD,ARG @@ -4072,7 +4072,7 @@ Sorts the LIST and returns the sorted list value. If SUBNAME or BLOCK is omitted, C<sort>s in standard string comparison order. If SUBNAME is specified, it gives the name of a subroutine that returns an integer less than, equal to, or greater than C<0>, depending on how the elements -of the list are to be ordered. (The C<E<lt>=E<gt>> and C<cmp> +of the list are to be ordered. (The C<< <=> >> and C<cmp> operators are extremely useful in such routines.) SUBNAME may be a scalar variable name (unsubscripted), in which case the value provides the name of (or a reference to) the actual subroutine to use. In place @@ -4168,7 +4168,7 @@ Examples: || $a->[2] cmp $b->[2] } map { [$_, /=(\d+)/, uc($_)] } @old; - + # using a prototype allows you to use any comparison subroutine # as a sort subroutine (including other package's subroutines) package other; @@ -4465,7 +4465,7 @@ the F</dev/urandom> device) or based on the current time and process ID, among other things. In versions of Perl prior to 5.004 the default seed was just the current C<time>. This isn't a particularly good seed, so many old programs supply their own seed value (often C<time ^ $$> or -C<time ^ ($$ + ($$ E<lt>E<lt> 15))>), but that isn't necessary any more. +C<time ^ ($$ + ($$ << 15))>), but that isn't necessary any more. In fact, it's usually not necessary to call C<srand> at all, because if it is not called explicitly, it is called implicitly at the first use of @@ -4587,7 +4587,7 @@ The commonly available S_IF* constants are S_IRWXU S_IRUSR S_IWUSR S_IXUSR S_IRWXG S_IRGRP S_IWGRP S_IXGRP S_IRWXO S_IROTH S_IWOTH S_IXOTH - + # Setuid/Setgid/Stickiness. S_ISUID S_ISGID S_ISVTX S_ISTXT @@ -5203,8 +5203,8 @@ and then there's sub ordinal { unpack("c",$_[0]); } # same as ord() In addition to fields allowed in pack(), you may prefix a field with -a %E<lt>numberE<gt> to indicate that -you want a E<lt>numberE<gt>-bit checksum of the items instead of the items +a %<number> to indicate that +you want a <number>-bit checksum of the items instead of the items themselves. Default is a 16-bit checksum. Checksum is calculated by summing numeric values of expanded values (for string fields the sum of C<ord($char)> is taken, for bit fields the sum of zeroes and ones). |